Arrangement in high-tension disconnecting switches



H. FORWALD July 24, 1951 ARRANGEMENT IN HIGH-TENSION DISCONNECTING SWITCHES Filed Jan. 17, 1948 Patented July 24, 1951 ,TES A NT- OFFICE;

' 2,56;027' J g. "1" IN moH-TENsIoN'DIs- I TING s wr'ronns n5. on; ald,-Yalhal l ,Ludvika'sivcden'as slgncr t Allman-na Svenska Elektriska,,Akt1e s j swedemaswedish p0 i A mee in Application January 17, 1 948 Seria- In Sweden @1113 25, 1946;

Section 1, Public Law ssan gcsft s Patent expires July 25,1966

3 Claims. (Cl. 200-48) 1 2 In electric disconnecting switches having a is an opening ll through which the contact movable contact arm engaging a stationary conhorns 4 project, and by the spring I the contact, the motion of the arm is frequently pretact horns are forced against the lower edge of vented by, for example, an ice formation at the the opening H, the upper and lower extremities contact point, or when the contacts have been 5 of said opening ll serving as upper and lower welded together due to an arc formation bestops for said horns. The current is delivered tween them. To facilitate the motion of the to the contact horns by the flexible connection 8. contact arm when such ice formation or weld- When the contact attached to the arm I and ing has occurred, disconnecting switches have the contact horns 4 become welded together, been so designed that when the switch is opened or when by other causes a sufiicient friction there is a rotating component in the sliding moexists between the contacts, the contact horns tion between the contact surfaces. Due to this are raised when the arm I is moved upwards, rotating component between the surfaces, the until said horns reach the upper stops or end ice or weld is readily broken so that the opening position determined by the edge l2, which posimotion may be readily performed. In a known tion on the drawing is indicated by dotted lines form of disconnecting switches, this rotating in Fig; 1, and there will thus be a rotating comcomponent between the contact surfaces has ponent in the sliding motion between the conbeen obtained by arranging the stationary contact surfaces when the switch is being opened. tact to swing in the same plane as the contact This arrangement has the advantage that the arm around a pivot located at a distance from contacts, when closing the switch, smoothly enthe contact point. In the known form, the stagage each other, due to the fact that the contact tionary contact is actuatedby a spring acting surfaces on the stationary contact horns are in the same direction asthe force exerted on parallel, and when the-contact arm enters beit by the frictional force from the contact arm tween them, are moved sidewise onlya very small when the switch is opened. distance, and due to the fact that the stationary According to the present invention, the spring contact device rests against the lower stop, there acting on the swinging stationary contact is so will be no rebound when the contact arm reaches arranged that it normally forces the swinging the stationary contact with great velocity.

contact against a lower stop, and further, the I claim as my invention: I

stationary contact consists of two parallel con- 1. An electric disconnecting switch comprising tact horns forming a vertical contact gap, the a swinging contact arm, a movable contact sesaid horns being actuated by springs and being cured to the free end of said arm, two parallel held in such a position in relation to each other ang'ularly bent contact horns having substanthat the distance between them is less than the tially vertical and substantially horizontal leg breadth of the movable contact, and the horns parts an rv n as th tati nary ont ct doare forced sidewise by the movable contact when vice for engagement with said movable contact,

it enters the contact gap. said vertical leg parts forming a vertical con- On the accompanying drawing, Fig. 1 is a side tact gap, a pivot arranged perpendicularly to view of the disconnecting switch, partly in secsaid horns and secured to said horizontal le tion, and Fig. 2 is a cross-section through the 40 p an insulator, journals for d D v a movable contact of the switch, showing engageried by said insulator, upper and lower stops for ment thereof between the stationary contact said horns, and a spring normally forcing said horns. I 1 horns against the lower stop, and having one On the drawing l designates the disconnecting end connected to said insulator and. the other .switch arm, which is pivoted in a support 2 atend connected to said horns.

tached to the insulator 3. The swinging of the 2. An electric disconnecting Sw p sarm is effected by a device not shown on the ing a Sw C nt a p of spaced drawing. The stationary contact 4 of the dism m ers f rmin a n m ll t ary n t connecting switch consists of two horns 4, each for e m nt by the free end of said swingin consisting of a bar bent in an acute angle, one 00 contact arm, a pivot arranged perpendicularly leg of each horn being secured to a block 5 movto sai p c m m er an ab t which aid able on a pivot 6, while the other legs, which members may turn when said contacts are being are parallel to each other, form a vertical condisengaged from each other, an insulator suptact gap. The pivot 6 is journalled in a cap 9 p rting said pivot, a p device holding a attached to the insulator III. In the cap 9 there members in their normal stationary position and preventing yielding movement of the said members while being engaged by the swinging contact, arm, iaxspr ing having one end stationary and the other end connec'ted to the-spaced members whereby said members are yieldingly held against said stop device, and a second stop device spaced from the first :stqp device -andadapted to limit the movement of the said spaced members when the contacts are being disengaged from each other.

3. An electric disconnecting switch, according to claim 2, comprising a cap mounted on said insulator, journals in said cap for said pivot, and a slot in said cap, the extremities of said slot forming said stop devices for limiting the 15 movement of said spaced contact members.

HAAKON FORWALD.

4 1 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 361L082 Wightman et a1. July 26, 1887 477,374 Klein June 21, 1892 1,463,320 Jacobs July 31, 1923 1,901,493 Bowie Mar. 14, 1933 ;2';194,021 Johnson Mar. 19, 1940 2,248376 Johnson July 8, 1941 Frank et a1 Aug. 19, 1947 

